const arr = [1, 3, 4, 5];
let result = sample(arr, 2);

expect(result.length).to.equal(2);
for (let i = 0; i < result.length; i++) {
    expect(arr.indexOf(result[i])).to.not.equal(-1);
}

const obj = { a: 1, b: 2, c: 3 };
result = sample(obj, 1);
expect(result.length).to.equal(1);
